The present invention relates to a rotary wing aircraft main rotor blade, and more particularly to a main rotor blade with a cuff integral with the spar.
Rotary-wing aircraft rotor blades often include a composite or metallic main rotor spar of a constant chord and constant wall thickness. To attach the rotor spar to a hub assembly, a separate root end cuff is attached to an inboard section of the main rotor spar. The cuff is conventionally manufactured of a titanium forging or a composite root laminate sized to match an outer mold line of the main rotor spar. The root end cuff is attached to the main rotor spar through a multiple fastener configuration, each fastener of which must be torqued to a required standard.
Although effective, the separate root end cuff assembly and related hub componentry may result in a weight and life cycle penalty as the multiple of components are duplicated on each rotor blade assembly.